The Omnisensor was created by Artemis Fowl II. It was the fairy communicator given to him by Holly Short, plus a few modifications and add-ons made by Artemis himself. The phone is the size and shape of a quarter with a pulsing red crystal at its center. It can interface with any communications system, including the human body. The phone was disguised as a rather ostentatious ring on Artemis's middle finger. Artemis twists the ring so that it sits on his palm, then closes his middle fingers, extending his thumb and little finger. The sensor would decode vibrations in his little finger and send them as voice patterns. It would also use the bones in his hand to transmit the caller's voice to the tip of his thumb. Only one person can call him by this, and that is Captain Holly Short.